Thread: Hand made sash clamps

Now that I've finally decided upon a design (yes, a roubo) and sourced some lumber (old hardwood from a salvage yard in North Melbourne) I want to start building a proper workbench, at last. You can see the "workbench" I've been using in the picture.

However, before I do that, there's one more thing I need - a collection of sash clamps.

The workbench will be 6" long (or a bit longer, if I can fit the lumber in the car). I'm not really sure how many sash clamps I need. What do you think, oh wise ones?

Whatever that number is, it's more than I can afford. Good new clamps are seriously expensive, and second hand ones (although much better) are hit-and-miss and are difficult to find.

So I decided to build some.

This design is a composite of a few other ideas I've found on the interwebs.

The beam is a 90x45 construction grade Radiata plank. The solid foot is attached with a tight cross-lap joint, reinforced with screws. A small mortise in this piece holds a 1/2" nut, epoxied in place with JB Weld. The moveable stop is held in place by a small length of 1/2" threaded rod. The moving foot also contains a 1/2" nut, but this nut is glued onto the rod (not the housing) and allowed to turn within the mortise as the rod does. A piece of aluminium prevents the nut from breaking through into the work piece.

This is a rough and ready prototype, and was done with hand tools - and no proper bench. However, I am really surprised by how well it works. It can really clamp down hard, until it's difficult to tighten any further using even a large wrench. I haven't managed to break it yet, and I've tried.

Do you think that a bunch of these would be adequate to laminate a hardwood workbench top?